As the countdown began on Aug. 5, 2011 at the Kennedy Space Center in Florida, all eyes were on the Atlas V Launchpad. In the crowd that day were the scientists and engineers from San Antonio's Southwest Research Institute (SwRI) Space Science and Engineering Division. Hearts thumped and excitement mounted as years of hard work were coming to fruition. That day, Atlas V’s payload, Juno, led by SwRI Associate Vice President Dr. Scott Bolton, would begin its five-year journey to Jupiter.
Teams from SwRI and other organizations around the world will converge on NASA’s Jet Propulsion Lab in Pasadena, Calif. this weekend when Juno finally reaches its destination. On Monday, July 4, Juno will use Jupiter’s gravity to pull it into its orbit, and will begin 14 months of scientific exploration.
Juno, like the goddess for whom it is named, will reveal Jupiter’s secrets.
Proposed in 2004 as part of NASA’s New Frontiers Program, Juno will bring information not only about Jupiter, but also will provide insight into the origins of the solar system. When the sun formed, it left behind large clouds of gas and dust. The planet is made of these gases – hydrogen and helium. It was the first large gas planet to be formed, so understanding this planet will provide clues about the evolution of the solar system. Does it have a rocky core? How much oxygen is there? What drives the planet's strong magnetic field? Is there water?
It’s not easy to travel 365 million miles in five years, so two years into its journey, Juno got some help from Earth.
“Using Earth’s orbit to gain speed, it got a boost using Earth as a sling shot to propel it further towards Jupiter,” explained Scott Weidner, Southwest Research Institute Engineer and Program Manager for one of the instruments on board.
Now, Juno is rapidly approaching Jupiter and must prepare for insertion. As it approaches the planet, it will turn around and fire its main engines for 30 minutes, slowing down enough to get pulled into Jupiter’s orbit.
Not only is Juno exploring new worlds, the scientific knowledge that built it created new standards. Getting into Jupiter’s orbit has risks, and the radiation belt surrounding the planet is highly destructive, particularly to sensitive electronic equipment on spacecrafts. The team got around this by designing a titanium vault to shield the electronics. The design, used first on Juno, is now the default for NASA missions. Juno’s path will bring it in from the north and travel south, where it’ll skim the radiation belt by flying very close to the planet, further protecting the electronics and going close enough to the planet to collect scientific data.
In the SwRI labs and conference rooms on San Antonio’s Westside, scientists and engineers spent years discussing, designing, developing, and building two of the 10 instruments that make up Juno’s payload.
Imagine the Northern Lights in Alaska. Now imagine the lights larger than the entire Earth. That’s what Jupiter’s auroras are like, according to Dr. Randy Gladstone, SwRI scientist and lead of UltraViolet Spectragraph (UVS). Gladstone has been interested in the study of auroras since graduate school. With his experience developing a similar instrument for New Horizons, the mission that flew by Pluto last summer, he was ready to lead the Juno-UVS team.
Jupiter, like Earth, has a magnetic field around it – a magnetosphere – filled with particles. This spectrograph will look at ultraviolet light in the magnetosphere, breaking it up into multiple "colors." The different colors give information about Jupiter’s upper atmosphere.
Another SwRI team is also studying Jupiter’s aurora with the Jovian Auroral Distributions Experiment (JADE). JADE measures the particles in Jupiter's environment that cause the auroras and those that Jupiter’s volcanic moon Io has dumped into the planet’s huge magnetosphere releasing charged particles, said Weidner, Program Manager for JADE.
“The magnetosphere is the largest in the solar system, the tail stretches all the way to Saturn’s orbit,” he said.
When the particles ram into the atmosphere, they’re visible as bits of light, forming the aurora. JADE’s three sensors look in three different directions at all times, allowing it to continually collect information on those particles. The information gathered will help scientists understand Jupiter’s magnetosphere and see how it differs from that of the Earth.
With 10 instruments collecting data and scientists based around the world, sorting data and organizing it can be a challenge. That’s the job of Prachet Mokashi, Juno Science Operations Center (JSOC) Manager and SwRI Program Manager.
“Juno will travel across the poles of Jupiter collecting data, making 36 orbits of 14 days each,” Mokashi said.
The solar-powered mission, traveling so far from the sun, has limited power. So their job is to coordinate the instruments and make sure they’re turned on and off when they’re supposed to be. Once the data comes back, the instrument teams put it into a useable form and send them to the JSOC. The JSOC team will sort it and make it available to all the scientists working on Juno. After the scientists have a chance to review it, the JSOC will make the data available to the public.
Among the seasoned scientists and engineers at SwRI, UTSA graduate students in the Space Physics program also have the opportunity to participate in missions like Juno. Jenna Zink, who interned at NASA for two years during her undergraduate studies in physics, said her NASA colleagues told her, “You must go to SwRI/UTSA for your PhD.”
When she arrived at the research institute last fall, she was assigned to JADE. Working with her SwRI mentors, her role is to perform test runs on the monitors which will ensure that when real data starts to come in this summer, they’ll be able to use it.
“It’s unbelievable," she said, "within a month here, I was touching stuff that’s going into space.”
While Juno cracks Jupiter’s secrets, scientists will gain insight into not only Jupiter, but also our solar system. Meanwhile, back on Earth, San Antonio scientists and engineers, along with their students, are making it happen.
Update: To watch Juno's insertion into Jupiter's orbit, go here.
Top image: Artistic depiction of Juno. Photo courtesy of NASA.